This volume collects the published essays of the late Professor Hourani on Islamic ethics in the earlier classical and formative periods of Islamic civilisation. Ethics was from the start at the core of Islam, and the construction of philosophical theories to support normative ethics made those centuries among the most profound and intensely active in the history of ethical thought. The book opens with two general and contextual pieces and thereafter it is organised by schools of thought in a broadly chronological order. The essays centre around two related debates in Islamic philosophy: over the ontological status of value, and over the sources of our knowledge of value. The answers developed follow similar lines to the rational theology and philosophy of the West, and Professor Hourani brings out the frequent parallels. As a whole, the volume will introduce and establish the importance of the Islamic tradition of thought about ethics.